1. Field of the Invention
The present invention relates to servomechanisms and more specifically to electronically simulated servomotors for use in designing servomechanical systems.
2. Description of the Prior Art
The development of a complex servo system often entails the construction of a laboratory prototype in which the control portion of the system actuates a servomotor that drives a physical load having the same properties as the mechanical system to be driven in the finished product.
For example, in the development of aircraft autopilot systems, the autopilot portion of the system develops position control signals which are applied to electric servomotors. Mechanical apparatus is used to apply a load to the motor shaft that mimics the load experienced in an actual flight environment. The mechanical apparatus is designed to place a predetermined spring load on the servo shaft to simulate aerodynamic hinge moment loads that increase in proportion to the surface displacement of the mimicked load. To change the spring gradient from one flight condition to another requires cumbersome adjustment since a given setting is only valid for one flight condition. The complexity of the mechanical apparatus is directly proportional to complexity of the simulated mechanical system, increasing in size, weight and cost as the mechanical system complexity increases.
The servo simulator of the present invention replaces the mechanical apparatus and servomotor of prior art systems with an electronic system that mimics the dynamic response of the conventional servo/load apparatus.